Two-dimensional GeP₃ as a high capacity electrode material for Li-ion batteries

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Two-dimensional (2D) materials offer high surface area for lithium (Li) electrodes.
• Developing advanced anode materials is crucial for high-performance rechargeable lithium batteries.

Purpose of the Study:

• Investigate the adsorption and diffusion of Li on 2D GeP3 using DFT calculations.
• Evaluate 2D GeP3 as a potential anode material for Li-ion batteries.

Main Methods:

• Density Functional Theory (DFT) calculations.
• Analysis of Li adsorption sites and diffusion barriers.
• Estimation of theoretical capacity and voltage profiles.

Main Results:

• Identified favorable Li adsorption sites on 2D GeP3.
• Observed a semiconducting to metallic transition upon Li adsorption, indicating enhanced conductivity.
• Calculated a high theoretical capacity of 648 mA h g⁻¹ for GeP3, nearly double that of graphite.
• Determined a low diffusion barrier (~0.5 eV) and low average open-circuit voltage (~0.4 V).
• Observed minimal lattice expansion (1.2%) during Li intercalation.

Conclusions:

• 2D GeP3 is a promising candidate for next-generation lithium battery anodes.
• Exhibits ultrahigh capacity, superior ionic conductivity, and low voltage, surpassing current graphite anodes.
• 2D phosphides represent a new class of advanced materials for rechargeable lithium batteries.